Sung-Kit Yip

Publications (3)0 Total impact

• Source

  Available from: ArXiv

  Article: Trapped Resonant Fermions above Superfluid Transition Temperature

  Chi-Ho Cheng, Sung-Kit Yip
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  ABSTRACT: We investigate trapped resonant fermions with unequal populations within the local density approximation above the superfluid transition temperature. By tuning the attractive interaction between fermions via Feshbach resonance, the system evolves from weakly interacting fermi gas to strongly interacting fermi gas, and finally becomes bose-fermi mixture. The density profiles of fermions are examined and compared with experiments. We also point out the simple relationships between the local density, the axial density, and the gas pressure within the local density approximation.
  12/2006;
• Source

  Available from: ArXiv

  Article: Pairing Symmetry in the Anisotropic Fermi Superfluid under p-wave Feshbach Resonance

  Chi-Ho Cheng, Sung-Kit Yip
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  ABSTRACT: The anisotropic Fermi superfluid of ultra-cold Fermi atoms under the p-wave Feshbach resonance is studied theoretically. The pairing symmetry of the ground state is determined by the strength of the atom-atom magnetic dipole interaction. It is $k_z$ for a strong dipole interaction; while it becomes $k_z - i \beta k_y$, up to a rotation about z, for a weak one (Here $\beta$ < 1 is a numerical coefficient). By changing the external magnetic field or the atomic gas density, a phase transition between these two states can be driven. We discuss how the pairing symmetry of the ground state can be determined in the time-of-flight experiments.
  02/2006;
• Article: Fragmented and Single Condensate Ground States of Spin-1 Bose Gas

  Tin-lun Ho, Sung Kit Yip
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  ABSTRACT: We show that the ground state of a spin-1 Bose gas with an antiferromagnetic interaction is a fragmented condensate in uniform magnetic fields. The number fluctuations in each spin component change rapidly from being enormous (order N) to exceedingly small (order 1) as the magnetization of the system increases. A fragmented condensate can be turned into single condensate state by magnetic field gradients. The conditions for existence and method of detecting fragmented states are presented. In this paper, we address the question of whether the ground state of a Bose gas with internal degrees of freedom is what one normally expects, i.e. a state with a single Bose condensate. We shall show that this needs not be the case, and that experiments on optically trapped 23 Na spin-1 Bosons can help to uncover many highly unusual yet fundamental properties of Bose systems with internal degrees of freedom. Back in 1956, Penrose and Onsager [1] succeeded in generalizing the concept of BoseEinste...
  07/1999;